1. Field of the Invention
The present invention generally relates to a package material, more particularly to a manufacturing method of an eco friendly foam package material, which is biodegradable and which has compost characteristics.
2. The Prior Arts
As long as the economic development is concerned, more attention is paid on use of global resource and environment protection. Even through disposable tableware made of the expandable polystyrene (EPS) has better heat/cold preservation effect than those made of paper, and the buffer materials made of foaming expandable polystyrene are widely used in package of household appliances, precision instruments, computers, and electrical devices. However, EPS is a polymer material, which is not biodegradable and which cannot be fully recycled. Since EPS is made from oil which is a non-renewable resource, and results in the environment pollution, such that the application of package material, which is not biodegradable naturally and which cannot be fully recycled, and hence the usage thereof is limited and will be knocked out finally while more attention is paid on the environment protection and environment pollution.
Since the EPS foaming plastic material is one product that can pollute the environment and is facing to be knocked out, and the package and lining materials made of paper pulp are the main succedaneum nowadays. The package and lining materials made of paper pulp have disadvantages of low impact resistance due to the fine micro structure, wherein the impact resistance is affected by the geometric structure of product. Nowadays, the package and lining materials made of paper pulp is only manufactured as small-sized wadding due to the limiting of molding and manufacturing method, and the large-sized wadding and filling material for large-sized household appliances are still made of EPS. Moreover, the cost of the package and lining materials made of paper pulp is much higher than those made of EPS, such that the development of the package and lining materials made of paper pulp is restricted.
Polylactic acid resin is a biodegradable material disclosed in prior art, such as Taiwan Patent No. 1318996 and Taiwan Patent Publication No. 200716708, however, those prior arts do not describe the foaming method for polylactic acid resin and the polylactic acid resin is not applied in buffer package material. Taiwan Patent No. 1280869 disclosed a foaming technology, however, it does not describe the application in biodegradable material, and it is noted that the processing is a chemical foaming method, and the method would pollute the environment.
Therefore, a green and eco friendly foam package material manufactured by non-pollution processes to replace the EPS and to meet the environment protection trend of 21 century is required.